A bracket device for a track assembly. The bracket device includes a bracket member, a latch member and a retaining member. The bracket member includes a hook extended therefrom and adapted to connect with an assembling hole of a rack. The latch member includes a stop extended therefrom and movably received in a slot of the bracket member. The retaining member includes an engaging portion adapted to engage/disengage with/from an engaging portion of the latch member.